


Living Your Beast Life

by GluttonyBiscuits



Category: Undertale (Video Game)
Genre: Alternate Universe - BeastTale (Undertale), Alternate Universe - Underfell (Undertale), Awkward Flirting, Awkwardness, Everyone Has Issues, M/M, Masturbation, Other Additional Tags to Be Added, Red has Issues, Sans Has Issues, Sans and Red are totally different species of skeleton, Sanscest - Freeform, Self-Esteem Issues, Self-Hatred, Slow Burn, Strangers to Friends to Lovers, it's gon be really gay, kustard - Freeform, no universe hopping here folks, pillow humping, there's literally no tag for that?, trust me - Freeform
Language: English
Status: In-Progress
Published: 2020-09-27
Updated: 2020-12-06
Packaged: 2021-03-08 02:07:50
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 3
Words: 9,013
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26687914
Author URL: https://archiveofourown.org/users/GluttonyBiscuits/pseuds/GluttonyBiscuits
Summary: ((Will be adding character and relationship tags as this gets updated! Don't wanna get y'all's hopes up))Monsters have been sealed away and abandoned by Humans for over two thousand years. During those exiled times, Monsters evolved and got accustomed to live without sunlight. One of the very early evolution traits that developed was survival instincts.Slowly that trait became unheard of, until only one Monster survived to create two very special offspring.
Relationships: Kustard, Sans (Undertale) & Sans (Underfell), Sans (Undertale/Sans (Underfell), Sans/Red, Sans/Sans (Undertale)
Comments: 15
Kudos: 42





	1. Snow-Bound

**Author's Note:**

> Okayokayokay listen before you get your pitchforks and lighters out!  
> I know I said I would be doing a sort of mini series for both YTATMP and ATOS, but my heart has been craving for some gay Kustard y'know? A person needs some squishy skeleton feels aaaaaaa,,,,
> 
> This fic was beta-read by the lovely [Armelle22](https://archiveofourown.org/users/armelle22/pseuds/armelle22?s20) ! Go give them a gigantic hug and give them lots of praise for their amazing work!
> 
> Anyway, yeah so hopefully I'll stick with the commitment of continuing to write for this story (unlike Camellia but we don't talk about that here-)  
> I hope you enjoy what comes after this block of text, and stay safe out there! Wash yo damn hands for the love of Stars, we all know you've been sticking your nasty fingers in that bowl of ice cream!

~ Chapter One | Snow-Bound ~

White magic slowly floated down from the cavern ceiling and piled up onto the floor, leaving a fresh canvas for anyone willing to play outside in the winter-y hell. There was a reason why most monsters migrated onward instead of staying in the cold forests of Snowdin. He stopped counting the number of times the magic snow went into his eye sockets or nasal cavity. Sure, it was relaxing to look at from inside a building, but outside it could get fucking freezing even when Red was wearing his fluffy jacket.

He wished multiple times throughout his life that the "cold goes right through you" joke was true.

The stout skeleton grumbled to himself as he walked away from the Ruins' doors, ready to take a much needed nap on the couch. He didn't care if Edge caught him dozing on duty. Future him could deal with it. He walked half a mile just to exchange some cheesy knock knock jokes to that old lady, a short snooze was all he was asking, damn it.

Red felt a small pebble underneath his sneaker and halfheartedly kicked it in front of himself like a playing ball. It was until the skeleton got to the gates Edge stupidly built that he heard leaves rustle from the trees nearby. Red appeared nonchalant to the noise, but inside he was freaking out, his SOUL anxiously thrumming underneath his ribcage. Was it a wild animal starving for Monster dust? What if the ambusher was a vengeful Monster ready to tear his bones apart? Stars knew just how many were waiting for that moment to strike and boast about having Lieutenant Edge's brother's dust on their hands.

The rustling stopped after a few seconds, and Red had to strain his hearing in order to stay alert. To his left, he pinpointed the intruder and used his blue magic to grab their SOUL, his left eye blazed with a dangerous ruby flame. A loud yelp escaped from the Monster and the sound of feet scampering across snow and dirt resounded in their general direction as they tried to get away from Red's grasp, but to no avail.

An indigo glow bounced off the forest foliage as Red's ambusher was dragged closer. He stopped pulling once he realized who was before him. Almost a head shorter than himself stood another skeleton Monster. Unlike Red though was their skull shape, made to appear as an animal skull rather than a Human's, and a long skeletal tail that thrashed around in frustration. They also stood on all fours like a canine.

Red got over his awe and scowled at his stalker. "th' hell you doin' followin' me like dat? ya coulda been dusted if i attacked ya first."

The opposing Monster growled loudly in retaliation, their left eye socket flickering with an electric blue spark. Red had to admire their non-existent guts. However, one step was all it took for the skeletal beast to cower slightly, though the vertebrae on their spinal cord still stood upright. Looked like they knew who was really in charge.

"why're you all th' way out 'ere anyway? ya fittin' ta be free EXP?" Red chuckled at his own morbid joke and yanked the Monster's SOUL forward with a flick of the wrist. The other skeleton dug their front claws into the snow to keep themselves stable. "what's yer name anyway? might as well help ya home, don't have anythin' better ta' do."

The shorter skeleton took a minute to respond, their dilated eye lights flickering in suspicion. "sans."

Red noted to himself that the opposing skeleton was a lower case just like himself. Skeleton Monsters were notorious for using font based magic to manipulate the "scrolling" of their speech. Red, and now Sans, were lower case Monsters, meaning they naturally spoke slower and have deeper and quieter voices. Of course they can choose to talk faster or louder, but both of them were too lazy to put in that much effort into something so meager such as talking.

Red put most of his weight on his left foot and smirked at the other. "sans, huh? pretty cute name." Sans flushed a light blue around his muzzle at the small compliment. "'m red."

Red dropped his gravity magic from Sans' SOUL so he could stand up properly, trusting the other wouldn't scamper off. Red had a good three inches above him, but Sans could probably be around the same height if he stood on his hind legs. Speaking of, Sans rose to stand on them to dust off his indigo parka, and shook snow off from his bones. A cute pair of pastel pink slippers adorned his feet, and wore basketball shorts similar to Red's.

"so, where'ya headed, beast boy?" Red quipped. He stuffed his hands in his leather jacket and put weight on one foot, sizing Sans up. Now that he was looking closer, Sans' bones seemed much grayer than what was healthy, and he looked, ironically, pretty thin. Skeleton Monsters like Red use their magic to make themselves look "fuller" to an extent. It helped make them look like they have muscles, or some sort of depth to their structures. Sans looked like his clothes were simply hanging from his bones, not unlike a clothes hanger in a closet. His parka wasn't faring much better either, with a couple holes and rips near the bottom, like something tried to get a hold of Sans but failed.

"mm, got a place nearby i'm staying at." Sans scuffed a slipper in the snow beneath him, looking embarrassed. "'s pretty comfy."

Red just looked at the other skeleton with a raised bone brow, not buying the second part. He recognized a white lie anywhere. "ya, nope. yer not goin' back there."

"what are you talking about, i got nowhere else to go?"

Red just chuckled and made a hand gesture at Sans. "trust me, sweetheart, we're leavin' dat dump behind."

Sans stared at him instead, unblinking. Then he snorted and shook his skull. "you actually think i'm gonna follow a complete stranger out into the open where i'll most likely be dust the second i'm vulnerable? thanks, but no thanks, bud."

Now it was Red's turn to stare. Was the guy for real? He couldn't blame Sans for not trusting Red, they'd just met, after all. And the Monsters outside the forest weren't exactly the friendliest, including himself. He shrugged and turned away with a flourish to begin walking back home. "suit yerself, buddy. don' come crawlin' back ta me when yer dust mixes wit' th' snow." He laughed cruelly with a loud snort and waved back halfheartedly, the soft snow crunched underneath his sneakers pleasantly.

-

Sans looked at the back of Red's skull with a concentrated frown. It seemed the red eyed skeleton genuinely wanted to help by the shocked expression. He was just worried for Papyrus' safety, as the Monsters outside of the forest weren't the kindest. But, then again, he didn't exactly give them a chance, and Red seemed like a nice guy. Deception was key in the Underground, however. His brother's safety was his top priority, no matter how much both him and Papyrus wanted to move somewhere more secure. Though, was a shelter made from sticks, snow, and mud in the middle of a forest really that much safer than a house in an actual town?

Sans sighed in frustration and called out, taking a gamble at the dangerous game.

"hey, wait! red!" The skeleton in question looked back with a tilt of his skull, that one golden tooth reflecting the white magic around them. Sans huffed and gazed into the Snowdin Forest, eye sockets scrunched up in thought.

Sans would never forgive himself if Papyrus got hurt because of his paranoid mind running rampant. He needed time to think about this life changing decision he may or may not pass up. "'m not denyin' your offer, but i need some time to think on it."

Red smirked with a single bone brow raised, making the skeleton look predatory. Sans shivered, but he knew deep down that it wasn't from fear.

"i patrol beyond th' gate ev'ry day 'round this time. come find me if ya change yer mind." Red angled his head toward the wooden structure and Sans followed his line of sight. The opposing skeleton nodded once before getting on all fours and dashing into the forest foliage, weaving through bushes and trees with excellent precision. A few beats of silence passed by before Red glared at the snow beneath him and scoffed to himself, a light red glow dusting his zygomatic cheekbones. Only a Monster who had exceptional hearing could hear the stout skeleton mumble to himself, "get a grip, ya fuckin' bonehead."

-

Sans swiftly weaved through tall evergreens following an invisible path he memorized, his skeletal frame a blur to the unkeen eye. The forest was heavily dense due to the trees being so close together and snow piled on top of the canopy. Thankfully, Sans had his eyelights to see better in the dark. Monsters evolved with better night vision from living Underground for thousands of years, and Sans and Papyrus were no exception, but since they didn't have actual eyeballs including retinas and the pupil there was nothing stopping them from seeing clearly in any light level.

Four branches were laid out on the snow covered ground near their base, acting as a landmarker of sorts. Sans slowed to a stop near a small incline dug out as a makeshift cave, with an arch-shaped entrance similar to an igloo. Thin twigs, mud, and moist leaves protected the outer shell of the temporary house from collapsing. Papyrus built the majority of it. Sans smiled at his baby brother's hard work, and the thought of leaving behind the shelter swam in his skull.

Sans crouched to fit inside the hideout, dried leaves being shattered underneath his slippered feet. A quick glimpse around the room showed Papyrus drawing a small pattern in the snow with a small stick, most likely a blueprint for a puzzle he was working on. A concentrated furrow on his bone brows was plastered on his skull. The younger brother matched Sans' body structure with a natural four-legged stance, but could easily walk bipedal. Unlike Sans however, were small additions to Papyrus' silhouette, such as long curving horns atop his skull similar to a ram's. He was naturally lanky, but incredibly agile due to his exercising regimen he put on himself. He could be intimidating if you didn't personally know him, and Sans couldn't be prouder.

"hey, bro." Papyrus looked up and gave his brother a toothy grin, before turning back to his sketch.

"GOOD AFTERNOON, BROTHER! HOW WAS YOUR WALK?"

"actually, that's what i wanna talk to you about." Sans scratched the nape of his neck. Should he wait a couple days before he told Papyrus so Sans could figure out an answer for himself? No, he would never be able to hide that big of a secret from his brother. "how do ya feel about letting someone help us find a home?"

Papyrus whipped his head up so fast, Sans worried he got whiplash or cracked his cervical vertebrae. "WELL, WHAT ARE WE WAITING FOR, SANS?! LET'S MEET THEM! SURELY THEY WILL LOVE MY FAMOUS FRIENDSHIP SPAGHETTI I'LL COOK FOR THEM!"

The beaming grin he gave his older brother made Sans exhale a breath he didn't know he was holding. However, the older skeleton didn't want to bring Papyrus somewhere he didn't know, and he had an idea.

"alright bro, but we can't leave today since i'm still looking. 'm gonna hunt for some more food, 'kay?" Sans glanced back toward Papyrus and spotted the taller skeleton beaming an award winning smile, and the former shot a smaller one his way.

"BE CAREFUL OUT THERE, SANS!"

After exiting the miniature snow hut, he swiftly took in his surroundings before bounding off toward the edge of the forest. If Sans was going to catch up with Red on time, he needed to find the stout skeleton in a safe environment first. The last thing he needed was for someone to ambush him and get killed in the middle of a conversation.

Before Red left, Sans recalled the skeleton implying that he was working right now and that Sans could find Red beyond the strange wooden gate bridge. Sure enough, once Sans exited the thick evergreen forest he spotted the skeleton lying atop a sentry station seemingly asleep. Sans knew better, though.

After all, he himself was a master at pretending to sleep and getting away with doing absolutely nothing.

Walking up to the post, Sans made sure to keep his footsteps light to not appear as a threat to Red. Once he knew Red noticed him he strolled over at normal speed. "already change yer mind, eh?" Red quipped good-naturedly, his mandible resting on the sentry counter with a half-lidded gaze.

"have a deal for ya actually," Sans shrugged back. Red raised a bone brow at that, looking mildly interested, but managed to hide most of it. "you show me where me an' my bro will be staying, and i'll say if it's safe for him."

-


	2. Angry Lieutenant

**Summary for the Chapter:**

> He isn't actually angry, just annoyed at the predicament his brother put him in. The title just sounded badass lol

**Notes for the Chapter:**

> So, this is most likely going to be extremely slow updating considering what's going on in the world, my studies, and keeping my mental health in check. I'm sorry if this chapter post made you excited for how quickly I update, but unfortunately that isn't the case.  
> Again, I'm sorry if you were expecting something a little better than this, but you ARE reading a fic by me sjfbdjfbdbdh  
> Anyway, stay safe, everyone! Wash those hands, people! I'm watching you.

~ Chapter Two | Angry Lieutenant ~

Red's phone vibrated in short bursts inside his jacket pocket, signaling a call. He rolled his eye lights and bared his sharp teeth at no one in particular, and pulled the device out to see who it was. Red already knew who though, because no sane person would call him while he was clocked in. As he would either snap at them for waking him up, or ignore the call altogether.

The stout skeleton was leaning heavily against one of the many evergreens that lined against the path to the Ruins' doors, waiting for his "guests." The day before, Sans came up to him wanting to see the house for himself before making the choice of agreeing to live there. Of course, Red complied, but acted grudgingly about it. He still wasn't sure what Edge would think about the whole ordeal, and Red didn't want to give Sans hope. Speaking of hope, or the lack thereof…

"RED! YOU BETTER NOT HAVE BEEN SLEEPING!" Edge's rough voice echoed inside Red's skull irritably, making him growl. The stout skeleton learned at a young age to place the speaker at least five inches away from his skull, as Edge was an upper case skeleton. He naturally spoke much louder and had a higher pitch than his brother. Most of the time Red had to gain Edge's attention in order for Edge to listen to him because of how loud the tall skeleton could be.

"i wasn't! shit, ya don't gotta remind me how terrible mah sleepin' schedule is." Red rubbed the area above his nasal cavity in frustration. He knew Edge meant well, he really did, but it was so annoying to hear the much taller skeleton rant on and on about good sleeping habits. "why don't you get some nightmares an' see how it feels, huh?"

A quiet sigh left the receiver on Edge's side, which caused Red to pause.

"s...sorry, bro. forget i said anythi-"

"I Still Do Not Understand Why You Refuse My Help, Red." Edge made his voice much quieter than what was normal of him, which meant he was trying to be serious. Shit. Red kicked a pile of snow magic from underneath himself with a flat grin. "I Give You Chances To Ask And Yet You Act As If I'm Not Doing Exactly That."

"y'know it's not easy fer me, bro. 'preciate th' help if dat makes ya feel better." By now, Red stopped leaning against the tree and put his fluffy hood over his skull, trying to hide his pathetic tears trying to escape. Vulnerability was the key to being dust, was what he was taught. Edge had different morals, which was both a good and bad thing for Red. Good because he didn't want his baby brother to kill innocents just like he once did for free EXP, and raise his pathetic excuse for HP and LV. But, it was bad because...

Because Red was terrified he would lose Edge to a malicious murderer on a rampage, and he knew Edge wouldn't want to hurt them. Because, Edge believed those people could change their ways for the better. 'They started out good, so why can't they end good as well if they try hard enough?' was what Edge said to Red one day when they were sparring.

"tryin' takes too much work," Red mumbled under his breath, and he distantly heard his brother ask what he said. He ignored it in favor of telling Edge the current situation, rapidly wiping away his red tears. "'ey boss, two Monsters need a new home, is it cool if dey crash at our place fer th' time bein'?"

Some muttering from the other skeleton could be heard and Red rolled his eye lights for the thousandth time that day. He could make out the words, "MORE MOUTHS TO FEED", and "I DON'T GET PAID ENOUGH FOR THIS" and Red tried so hard not to laugh for his own coccyx. He was currently working at multiple jobs and _Edge_ was the one to complain about money?

"SIGH," he really said the word 'sigh', the fucking drama queen, "I _SUPPOSE_ TWO MORE WOULDN'T HURT OUR BILLS AND SCHEDULES. BRING THEM OVER IF THEY WISH TO STAY."

"thanks, boss, yer th' greatest," Red replied with genuine gratitude. Stars knew what face Sans would make to him if Edge denied.

Stars his face was damn cute…

"MAKE SURE YOU STAY AWAKE THE REST OF YOUR SHIFT, RED! I FUCKING MEAN IT!" With that statement, the line went dead, signaling the end of the call. Red rolled his eye lights again and put his phone back in his jacket pocket.

Contrary to the almost unbearable cold of Snowdin Forest, Red's body radiated magic induced heat, making the inside of his jacket and pockets warm. That was the benefit of being a Monster strong enough to generate that kind of magic almost 24/7. That didn't mean it was foolproof and no wind could touch his bones, however. He was ashamed to admit he started slightly rattling from the cold.

Red was about to lean back against the tree behind himself when he heard two hushed voices coming from the forest. One of them he recognized as Sans, the other he didn't know. It was nasally and a much higher pitch than both Red and Sans' voices. Sans never mentioned having any relations with anyone, but that wasn't at the forefront of Red's mind at the moment. He slowly traversed cautiously toward the two voices, carefully maneuvering around thin branches. Magic flickered around his left eye socket, his SOUL feeling like it was going to burst from anticipation.

Sans and the other Monster casually strolled out of the forest and onto the cleared path, the former noticing Red's presence first. "hey red, this is my younger bro papyrus. paps, red," Sans introduced.

Papyrus was tall. A little shorter than Edge, but that was impressive either way. Two large horns protruded from his angular skull, not unlike the much smaller horns on Sans'. The guy was the definition of intimidating, and it made Red almost back up. _'Almost'_ being the key word here, he wasn't a pussy. Papyrus' voice didn't match his silhouette in the least, which made Red calm down a little.

"HELLO, FELLOW SKELETON MONSTER! ARE YOU PERHAPS THE ONE WHO WISHES TO HELP ME AND MY BROTHER SEEK A NEW SHELTER?" An upper case, just like Edge. Thankfully Red didn't have any eardrums to burst, and even if he did he had to deal with his brother his entire life and had to get used to the volume. Sans will probably feel the same once the brothers meet Edge.

Red hoped that interaction goes well.

"'sup, papyrus? yeah, me an' mah bro agreed ta house you guys fer th' time bein','' Red shrugged nonchalantly as he walked right past them. He swiftly scanned the area to search for any eavesdroppers and found none, so he continued lazily strolling onto the path. Looking back at Sans and Papyrus, the stout skeleton found both brothers holding a small knapsack each and were resting on their backs. 'looked like neither had much possessions to begin with,' thought Red absently.

The sounds of Papyrus talking loudly to the shorter skeletons cancelled out the snow and the occasional twigs crunching underneath their feet. Red hoped they wouldn't grab any unwanted attention from EXP starving Monsters while on the way toward Snowdin Town. Stars knew how much Red wanted to be out in the snow for more than what was necessary. Don't get him started on the constant snow magic blowing into his nasal cavity making him sneeze every ten fucking seconds. What a way to give a first(?) impression.

-

Sans really hoped he made the right choice agreeing to live with Red and bringing Papyrus along. So far it seemed that way. Now Sans just needed Red's brother to be at least semi okay with this as well. The last thing his brother needed was an unsafe living environment.

After Papyrus calmed down enough to let the air around the three skeletons simmer and set into a comfortable silence, the walk into Snowdin Town wasn't all that bad. The shorter skeletal beast always appreciated the snow that gradually floated down from above. It seemed to always relax him somehow, even on his darkest days and the dreariest nights.

It was around a fifteen minute walk from the Ruins' doors to the entrance of Snowdin Town. The town's atmosphere wasn't exactly the friendliest, but it wasn't as hostile as Sans had expected. Many monsters that spotted the three skeletons gave Red a suspicious glare, but cowered back reluctantly when the former shot a harsher glance back. It most likely had to do something with Red's brother, Edge. The stout skeleton commented off-handedly before that Edge was part of the Royal Guard, and Papyrus was ecstatic to meet the infamously terrifying monster. Sans, not so much. It was already enough to hear a few stories coming from Red's mandible, but actually living with the guy? Sans just hoped to the stars above that he would never get on Edge's bad side.

Red's house was just near the edge of the opposite side of town, a quaint two story wooden cottage. A few strings of Gyftmas lights were hung up underneath the roof's shingles, blinking merrily. A generous amount of snow was piled on top of the triangular roof, but somehow never managed to slide off. One large green wreath was hanging from the front door, obviously handmade from the intricate weaving patterns flowing through the structure of leaves and twigs.

It looked like a home well lived in and cared for.

-

After entering the cottage, Red claimed that Edge was still clocked in at work and wouldn't be home for another hour. He then proceeded to show Sans and Papyrus a pair of guest bedrooms that sat across from each other next to Red and Edge's rooms. Papyrus practically sprinted on all fours up the wooden staircase to the room he chose (the one next to Edge and across from Sans' room) and locked himself in to organize the space however he pleased.

It took Sans a couple seconds for him to process what he saw before he began moving himself. When Red showed the house per Sans' request, the skeletal beast only caught glimpses of the interior from the outside. For some strange reason, Red never entered the cottage taking Sans with him and Sans never bothered asking why. This was the first time the latter was inside.

When first entering the house he was greeted by the scent of pine wood and sweet cherries, although very faint. His enhanced senses let him track where the cherry smell was coming from, but at the moment it felt like it was all over the place. Sans decided to let the thought slide and remember it later. Hopefully.

The carpet underneath his slippers were very soft and coarse at the same time. The individual fibers were thick enough to be seen by the keen eye, which was perfect for when Sans just wanted to nap on the floor. He had those urges sometimes.

The living room was what really caught Sans' attention. It held a fifty five inch flat screen television that was hung on the opposite wall of a lumpy green couch. The couch itself seemed to be calling Sans' name, and he had the strongest need to dive skull first into the cushions and roll around. But, he fought it and kept looking around.

There was a room opposite of the front door that supposedly led to the kitchen. Sans decided to leave it alone since he'll probably be dragged into the kitchen by Paps once his brother spots all the utensils. Then he could get a closer look.

The wooden floorboards that made up the staircase creaked underneath his weight as he climbed up to his room, and Sans worried if it would one day give under everyone's pressure. Although he highly doubted that. The cottage itself looked to be built way before even his time and was still going strong, so he had nothing to worry about.

The second floor of Red's house had dark oak floorboards instead of the carpet lining the living room. If he wasn't wearing any slippers or socks, Sans' claws would be making satisfying little clicking sounds on the polished wood surface. There were five total doors leading to different rooms. At the far end of the hallway was the bathroom. Since this was a Monster resident house, there was no toilet installed because Monsters don't excrete anything out of their bodies. Everything they eat and/or drink is used as energy. If anything does need to be expelled, Monsters can convert their magic energy into liquid magic and go from there. Whether it be sweat, saliva, vomit when drunk, extra appendages if the Monster so wishes, and semen.

Sans was getting sidetracked.

The four other rooms were bedrooms, and three of them have already been taken. Papyrus claimed the room nearest the bathroom, and the sounds of items being thrown around invaded Sans' ear canals. Red and Edge's rooms were the closest to the stairs, so that led to the bedroom opposite of Papyrus' and right next to Red's. As Sans walked over to his bedroom door, the smell of sweet cherries almost winded him from how potent it was. The scent was definitely coming from one of those rooms. Sans was sorely tempted to investigate where that alluring smell was coming from, but he knew that would be an invasion of privacy. Besides, he wouldn't be making a good first impression by getting caught with his snout in a room that he shouldn't have entered in the first place. Leaving it be would have to do for now. Even though it almost physically pained him doing so.

That smell was so incredibly sweet and mouth-watering.

As he grabbed his room's brass doorknob, Sans looked behind himself out of habit. Dark oak railings lined the open hallway to prevent any accidental falls into the living room. He gazed past the polished wooden beams connecting the railings to the floor and spotted Red in the living room lazily sprawled across the lumpy green couch facing the television. Red appeared to not be focused on the channel being broadcasted, if anything he looked to be nodding off. The couch itself was probably the most used item in the entire house, as the couch cushions had rips and tears in many places, some exposing the metal springs inside. Red appeared unaffected by it and yawned into his palm, eye sockets scrunching up like a satisfied cat in the sun. His deadweight (heh) body sunk into the cushions even more. In the middle of his action, Sans made full eye contact with those piercing red eye lights and was unable to look away.

A single sultry wink was all it took for Sans to bolt inside his new bedroom, skull ablaze with his blue magic.

As the skeletal beast leaned heavily on the wooden door to try and calm his beating SOUL, he heard Red cackle heartily from the living room, making Sans groan heavily into his hands in embarrassment.

-

It took less than ten minutes for both skeletal beast brothers to finish unpacking and moving into their respective rooms. Having only a couple pairs of shorts, one shirt, two pairs of slippers, and random mismatched socks really weren't all that much, Sans mused to himself.

The guest room itself was pretty much the same thing as the living room, just on a smaller scale. The carpet was one of the softest things Sans' feet had ever touched, and he was not afraid to admit he thought about rolling on the floor to feel the fibers thoroughly. The only other items in the room were a bed and closet.

The rest of the time waiting for Edge to come home from work was spent wandering around their new, hopefully more permanent home and getting used to all the space and comfortable flooring. Papyrus found the kitchen and started fanboying over all the utensils ('called it,' Sans joked internally) and later, over Mettaton on the television in the living room. Red mumbled something about him being a walking toaster oven, and Sans snorted in agreement. Papyrus didn't pay any attention to either.

While his brother was busy being enraptured by the star of the Underground, Sans was sprawled across half of the lumpy green couch, tail occasionally brushing the carpet lazily. Red took the other half with a couple centimeters separating their slightly folded legs, some twitching from both of them made their limbs brush against one another. Papyrus meanwhile was sitting cross legged on the carpet so close to the flat screen television that if it wasn't for their anatomy, Sans would be concerned for his eyesight.

Sans has never felt more relaxed in all his life. He would've never believed that he would end up in an actual shelter with a roof that theoretically wouldn't concave in on itself from gravity. That feeling didn't last long as the front door got slammed against the drywall, letting in the chilly air and snow magic. Sans was so startled by the noise that he almost fell off the couch. Red didn't seem fazed by it and Papyrus merely looked in the intruder's direction.

"'ey, boss," Red lazily drawled on his side of the couch. Sans looked toward the doorway in confusion at the word 'boss' and almost fell off the couch again.

The skeleton standing before all three of them had a giant scowl on their skull. Their stance reminded him of a soldier on duty, making them even more intimidating. 'that must be edge, red's brother,' Sans thought with minor distaste. 'who else would barge into his house with an attitude like that?'

"SO." Edge's voice boomed throughout the house, commanding attention. Definitely an upper case, similar to Sans' own brother. Sans internally winced nonetheless. Unlike Papyrus however, is how Edge has more of a rasp while Papyrus' voice was more nasally like he always had a Monster cold and his nasal aperture was clogged. Sans could confirm that Paps was perfectly healthy though. "THESE ARE THE MONSTERS THAT WILL BE STAYING IN OUR DWELLING FOR THE TIME BEING I SUSPECT, BROTHER?"

"yeeeep," Red drawled from his seat on the couch, looking nonchalant as usual. He was almost slurring his speech and his body appeared to sink even deeper into the cushions. Sans took a closer look at the stout skeleton's skull. Red's lines under his eye sockets seemed deeper than the last time they saw each other, and he was looking more tired all around. Red's permanent grin was slouching a bit, and Sans secretly hoped that wasn't his and Papyrus' doing, no matter how selfish the thought was. He was barely looking at the other skeleton, as Red's eyelights were almost drifting off into the distance. He must be really tired, Sans empathetically noted.

It was at that moment that Sans realized how much he liked looking at Red's face, and the skeletal beast almost slapped himself. He'd barely known Red for less than a week (his brother not even an hour!) and already he was developing confusing thoughts such as this? He needed to stop that emotional train fast, or else Sans will make living in Red and Edge's house an awkward experience for everyone.

Stars knew how much Sans would hate himself even more for ruining Papyrus' only chance at a semi-normal life.

Loud footsteps brought Sans out of his stupor and found himself face-to-face with Edge himself. The guy was at least six feet tall, and a few inches taller than Papyrus which surprised Sans. There was a large crack on the side of his skull, and his fangs made Edge's features even more intimidating. Stars, Sans really hoped he made the right choice for moving here.

"Smaller Skeleton Beast." Red's brother lowered the volume of his speech, although still continued to look down at Sans with an aura of superiority. Sans raised a bone brow at the tall skeleton's label and he clearly heard Red snort from beside him. Edge sent a glare his way but it appeared to do nothing as Red continued to snicker. Edge cleared his throat before speaking again. "I Believe You Are The One Who Agreed To My Brother's Suggestion To Share Our Home. Are You Aware Which Location In The Underground We Are Currently Located In?"

"boss, i found 'em in th' forests, o' course dey know where we are," Red replied sarcastically, who soon after got hit with a pillow to the face. Sans quickly looked back at Red's brother to see Edge's hand outstretched from throwing said pillow. How he obtained it in the first place, Sans would never know. The skeletal beast recovered from the brothers' interaction and decided to answer Edge anyway.

"yeah, me and papyrus were living in the middle of the snowdin forests for most of our lives. i came across red while hunting for somethin' to eat," Sans said a little sheepishly. It was still embarrassing to admit he and his brother never got to live in an actual house. The laboratory in Hotland didn't count as a 'house' to the skeletal beasts as that had been a long time ago. The smaller skeletal beast sometimes had trouble remembering what the living room even looked like. Sans looked over at his brother and found Papyrus looking at Edge with the most mystified look on his skull, with his jaw parted. It sort of reminded Sans of when they were younger and Paps used to look at him that way. Sans admitted to feeling a little jealous at that moment, and barely managed to not let his smile fall.

Edge made a "harumph" noise between his jaws and strode away, leaving the living room. His heeled boots made a clicking sound once he entered the tiled kitchen area and began rummaging around, most likely preparing to make food.

"WOWIE!" Papyrus exclaimed once Edge fully left the room. Red looked back at the television even though Sans knew he wouldn't be paying any attention to it. "YOUR BROTHER IS ALMOST AS COOL AS I AM, AND THAT'S VERY HIGH ON THE COOLNESS SCALE!"

Red shrugged slightly against the couch. "eh, he's a'ight. was raised by me so don' expect no'ing outrageous or somethin'." He stretched his legs before slowly getting up. The TV remote was closest to him, so he threw it at Sans before making his way up the staircase. Sans dodged the projectile in time before it could do any damage, sending a light glare Red's way. He shrugged again. "i'mma take a nap. try an' wake me once edge burns th' house down."

Red ignored the very harsh threats Edge sent his way and slammed his bedroom door shut.

Sans looked toward his brother and saw Paps rushing toward the remote with grabby hands, his long tail like a whip. Chuckling at his childish behaviour, Sans handed the device off to the taller skeletal beast before taking the entire couch to himself. A nap at the first protected shelter he and Papyrus ever lived in? Hell yes, and he was going to heavily abuse that fact as well.

With Papyrus effectively distracted by Mettaton, Edge cooking in the kitchen and occasionally humming to himself, and Red turning in for the night, Sans found no cons in shutting off his body himself. Snuggling into his fluffy parka, it took no time at all for Sans to succumb to the warm embrace of darkness.

-


	3. A Place To Call Home

**Notes for the Chapter:**

> I hope this chapter is suited well for your liking! I uhh,,,, changed the rating so don't be surprised by what you're about to read 👀👀👀👀👀👀👀👀
> 
> Hope you enjoy this chapter!

~Chapter Three | A Place To Call Home~

Edge's lasagna wasn't terrible, but Red could tell that Sans wasn't a big fan of his brother's cooking. From the skeletal beast's expression though, he ate stuff far worse and wasn't having any trouble scarfing it down with Papyrus far in the lead. Both brothers looked like they hadn't eaten anything in a week, which might have possibly been true considering their previous living situation. Whatever. As long as they didn't shit on Edge's cooking then Red's absolutely okay with holding in his own complaints.

After dinner was when living with two extra Monsters became weird. Papyrus came up to Red and asked him if they had any spare pillows and blankets for Papyrus and Sans to use for their 'nests'. At first Red thought a nest was another word for mattress or something, and was about to make a snarky response to the tall skeletal beast, but then out of nowhere Sans sidled up next to his brother and claimed it was just a massive pillow fort.

Now, Red had no trouble absolutely losing his mind at the thought of two grown-out-of-stripes Monsters making pillow forts, but then Sans made this creepy face at Red that effectively shut his trap. After that whole fiasco though, Red just shook his skull and retired for the night, slamming his door shut for the second time that day.

Edge was the one to deliver the blankets and pillows.

-

Learning how to live inside of an actual house instead of a hut in the midst of forest trees was something Sans had to get used to, and quickly.

For starters, he and Papyrus had their own rooms now and didn't need to share nests anymore. Their old shelter had one giant room with no dividers, as Papyrus was in a bit of a rush to get it up fast and no one had time to construct dividers out of sticks, mud, and leaves. That meant Sans and Paps had to share rooms _and_ a nest. Their biology wasn't meant to handle shared territories, but they made it work by changing the bedding each night.

The reason why it wasn't safe to share their nest was because of their instincts. Monster beasts immediately leave their family to survive on their own. It was part of learning how to dwell under Mt. Ebott. And that meant they weren't used to smelling their siblings' scents on their bedding.

It didn't matter if Sans and Papyrus were related. Being in one's territory, no less where they _slept_ , was taboo, ungrateful, and especially dangerous. Unless those Monsters were mated, which the two skeletal brothers weren't _thank you very much_ , then it would be more than okay to sleep together.

Sans hoped Papyrus didn't have nightmares anymore.

Anyway, the fear of one brother hurting the other went away for both when they found out they would be getting separate rooms. No more did they need to worry about more accidents from territorial problems, which made Sans incredibly relieved. He didn't care about himself, only his brother. And if Papyrus didn't need to carry that burden of dusting his bro accidentally, then Sans was hopeful too.

But that could be swept under the rug for now. The other thing both sets of brothers had to get used to was sharing an entire living space with complete strangers. Sure Red may have let them stay there, but that was only yesterday! Knowing someone and living with them were completely different things, and Sans could heavily understand that now.

At that moment though, both skeletal beasts thought the same exact thing:

Sans was so lucky as to be caught by Red while hunting.

-

Edge actually couldn't believe this. Looking at the living room with a giant scowl across his face, Edge stomped into the kitchen and over to the complex looking coffee maker.

The tall skeleton Monster thought Red was a mess, but both Red _and_ Sans put together was like the trash tornado Red kept in his dirty ass room but one million times worse.

...Okay, Edge was over exaggerating just a little, but his anxiety over cleanliness always won over. Red knew this! Red knew Edge had extreme anxiety over something so minuscule such as cleaning a room to make it _even more clean_. Edge never wanted his brother to change who he was, but he _did_ want Red to change his messiness! Looking back at the living room, Edge's hands shook, wanting that giant mess of a room to go away, but he promised both himself and his brother that whatever mess Red (and now Sans) makes, he has to clean it up himself.

Ugh, Edge needed another coffee.

While brewing the fourth cup of caffeine of Edge's day, his mind started drifting toward the new "houseguests" as Red put the term. Burdens were more like it. Okay, now THAT was too harsh.

Edge could see why Red wanted to save those two weird looking skeletons, though. Their bones looked sickly, their clothes raggedy (the shorter one even more so), and Edge knew his brother. That sleepy look Red gave Sans the other day was his, albeit pretty gross, bedroom eyes. He was not being subtle about wanting to get fucked by another skeleton, and Edge almost gagged.

Yeah, he really needed this coffee right about now.

-

Red actually couldn't believe what he was doing.

Actually, no, he one hundred percent found this coming (heh) when Sans began staring at him with those pretty white eye lights most likely thinking Red was tired. If that really was the case, which it must've been since Sans looked concerned of all things whilst staring, Red needed to upgrade his seduction weapon.

AlsothatcuteblushSanswassportingafterwardswassogoddamnadorableohmyStars.

Sans and Papyrus went outside of town to go hunt for food. They were able to eat precooked meals, but their biology made them prefer freshly hunted meat over grocery items and premade foods. Red was nonchalant about the entire ordeal and stated that he didn't care what the hell the two skeletal beast brothers came home with, so long as they cooked it thoroughly. When Red said he would eat whatever Sans would bring home, Red could tell he made Sans incredibly happy.

That made him happy too.

Edge went out to the store to buy more vegetables for the meal ahead, and that left Red home alone.

So now, here he was, humping his body pillow like the animal he wasn't, and thinking about his new housemate like a sex toy. No wonder nobody wanted to take him out on a date, he was disgusting. Thinking about a person he knew not even a week, fantasizing about how big Sans' cock would be, thrusting that ginormous dick into Red's awaiting asshole like the slut he was. Stars, was Red drooling?

"mmmmmh, fuck baby boy, yea slam dat juicy cock into mah cunt fuuuuck." The sounds of Red humping his pillow along with his mattress moving with him could be heard outside his room. Thank Somebody he was home alone, else Edge would've smacked Red upside the head for masturbating to thoughts of their houseguests. Not before vomiting in the background from hearing his older brother fucking said pillow.

Red formed an ecto-dick long ago, and the fabric of his pillow sliding along Red's magic made him moan deeply. Head tilted back, the stout skeleton slid three of his fingers into his awaiting and slicked asshole. That got him going, yelling "fuck" over and over again.

"ahh, shit, i'm cummin' sweetheart. cum in mah drippin' cunt fer me, sans. aahhh, FUCK SANS!" Next thing Red knew, he was ejaculating all over his body pillow, his bones slick with excess magic. It took Red a few deep gulps of unneeded air for him to breathe normally again, groaning to himself about how good that session was.

After his magic calmed down enough to put away his ecto-flesh, Red took off the pillow case and chucked it in his trashnado. He would wash it later. Now was relaxation time after that wild wanking session.

"ohh shit, dat was good," Red mumbled to himself. He stretched out his bones, blood red turtleneck riding up his ribs to show his spine and a part of his ribcage. Red has always been clingy after sex, whether it be a one-night stand or a masturbation session. He found it easier to leave right after having sex so he didn't wake up to an empty bed in the morning. It always chipped his SOUL a little each time it happened, but Red was sentimental that way. He hated himself for it.

Red hated himself for a lot of reasons. One of them being his infatuation with one of his housemates.

While Red was laying on his dirty and old mattress, his eyes started to drift shut. The last thing his mind thought about before he was graced with unconsciousness was a cute skeletal tail swishing behind a stout body.

-

All four of the skeletons' rooms had locks on the doors. That gave each one of them a sense of comfort and privacy when doing who knows what in their respective rooms. It was only after a couple more weeks that the two skeletal beast brothers became comfortable in their new home, and didn't feel obligated to use the door locks any time they did anything in their own room. Or, maybe that was just Sans.

Either way, it seemed that the four skeletons were starting to act more and more like friends rather than just housemates or acquaintances. One of few good examples of this is how Edge didn't let anyone be in the kitchen with him. He said he didn't like it when people "GET UP IN MY FUCKING SPACE" when cooking. But now, the tall skeleton occasionally let's one or two other house members wander around the kitchen when dinner time rolls around. He didn't have a reason as to why.

"RED! GET OUT OF MY KITCHEN RIGHT NOW BEFORE I SLAP YOU INTO THE NEXT GALAXY!" Right now wasn't one of those times. Red was feeling particularly devilish and wanted to drink all of the mustard in the fridge, including the bottles specifically used for sandwiches and hot dogs (Red and Sans separated their drinking condiments from the other ones). It wasn't the first time Red has done something similar to this, but Edge wanted to hope one of those times would be the last.

"aww, c'mon boss, y'know I ain't a drinker anymore," Red replied cheekily. "cut me sum slack, won'tcha?" He rose his bone brows mischievously at his brother.

Edge gave a look that read, 'are you fucking with me right now.' "OUT. _NOW!_ "

When Red stopped pestering Edge and inevitably exited the kitchen, he spotted Sans lounging across the green couch and typing away on his phone Edge recently bought him.

Red was extremely proud to say that he was Sans' first contact implemented onto the device.

"ya still addicted t' dat thing?" Red inquired to the skeletal beast. Said beast looked up from his phone and shot a small, but effective smile that made Red's SOUL flutter slightly.

"heh, can't believe this tiny thing's gotten me _wired_." A wink was passed between the two and Sans scooted up the couch to make room for Red. The first time Sans made a pun, it was like the gateways had opened for Red and they had done nothing but trade ridiculous puns to each other for the next two hours. Needless to say, Red was super hyped to finally have another pun lover in close proximity. Screw that kooky old lady behind the door.

Red found himself seated nicely next to the skeletal beast Monster he gladly calls his friend. Red took it upon himself to sit close enough to brush knees, but far enough away to have Sans be comfortable. Sans didn't say anything.

"you drink all the mustard again?" Sans asked in a mix of both amusement and curiosity. He did this cute little head tilt when he was confused that Red absolutely adored. "heard edge barkin' up a storm at you."

"yuuup." Red popped the 'p' for emphasis. Unapologetic as he was, Red didn't like it when Edge was mad at him. But this would pass as it always did. "mah bro always gets th' good shit."

"heh," Sans chuckled under his breath with a smile on his skull, but it seemed almost… melancholy? "you're lucky edge isn't going to hurt you." That caught Red off guard.

Now that Red was thinking about it, Sans was the more mysterious one out of the two beast brothers. Hell, Papyrus could be an enigma at times. The townsfolk of Snowdin most likely don't even know where Sans and Papyrus came from and might as well have popped into existence. Also, why were there two different kinds of skeletons? The old geezer never ranted to him about an entirely different looking and functioning skeleton. Looking at Sans now, Red was close enough to the beast Monster that he could make out the different divots and markings intricately placed around his skull. It almost looked like some sort of seal? A binding? But to what? Did Papyrus have the same markings as his brother? How has Red never noticed them before? Shit, his skull's swimming and it's starting to hurt.

"edge ain't gunna hurt nobody, sweet'eart." Red's head was turned away just enough to not see the light blue magic dusting across Sans' zygomatic cheekbones. "th' tall bastard's too kind f'r his own good."

"seems both our brothers are." Red follows Sans' line of sight and comes to the conclusion that he was looking toward Papyrus' room upstairs. The taller brother was currently playing with some action figures Edge didn't use anymore. Papyrus looked like he was seriously about to cry when he realized those toys were his now.

Both stout skeletons fell into a cozy silence with Edge banging around the kitchen in the background. Red could get used to this. And it seemed Sans felt the same way by the tilt of his skull and subtly knocking his patella with Red's own.

"DINNER IS READY! IF YOU ARE NOT HERE WITHIN THE NEXT FIFTY SECONDS YOU DO NOT GET A PORTION!"

"someone's grumpy t'day," Red winked at Sans, which in turn made Sans snicker silently.

-

"hey."

Sans watched amusedly as Red jumped slightly at his voice. He must've been real tired, Sans thought to himself.

"mmh," Red grumbled. Sans blushed lightly at how wonderful Red sounded when he just woke up. His voice was much deeper from lack of use, and a little scratchy. But maybe he just needed water. Did he need water? Oh Stars, should Sans ask if Red needed water? Was that considered a show of affection if you bring a glass of water to your friend? Affection might as well be a taboo Underground, and Sans did not want to make Red uncomfortable by asking him _if he needed water_.

_fuck it, i'm worried._

"h-hey." Sans cleared his non-existent throat and started again. "hey, need some water?" There, subtle enough to not be considered prying or accusing in any way, but strong enough to not seem too affectionate.

Red rubbed his eye sockets sleepily and yawned into his hand, trying to cover it up but failing. Red waved off Sans' concerns over his voice and stretched out his bones. "mmm, nah, 'm good. 'preciate it though."

An awkward silence stretched between the two older skeletons, an extreme contrast from last night. At least, it seemed awkward for Sans.

"welp." Red rose from his seat on the couch and started walking up the wooden stairs. "'m takin' a shower."

Sans almost slapped himself for what was about to come out of his mandible.

I can join you.

"i'm gonna cook breakfast this time," Sans replied instead. He was getting kind of tired of breakfast lasagna and half-cooked bacon. It seemed Sans was wearing his SOUL on his jacket sleeve as Red began snorting his way up the stairs and into the bathroom. It was long after the door closed and locked shut that the shorter skeletal beast realized he'd been standing in the middle of the living room for what appears to be around five minutes. He briskly walked into the kitchen to get started on breakfast.

Last night's dinner was scrumptious, with both Sans and Papyrus catching rabbits, Edge was able to make the best rabbit stew any Monster could ask for. Now, Sans wasn't a five star chef. But he did teach The Great Papyrus all he needed to know about cooking. The skeletal beast swiftly pulled out all the necessary ingredients and tools and got to work.

Sans never noticed Red silently watching him from across the living room, smiling like a dork in love.

.  
.  
.

Wait, what.


End file.
